# Invention of the airplane

```Invention of the airplane
Brittany Woodrow, Sam
Magliaro, James Hannah, Haram
Kim, and Younghun Wi
Prevailing View Before Discovery
If birds can fly, why not people?
•
Originally, engineers thought that when a bird's wings flapped, that motion
was what caused it to lift by forcing air downward.
•
Many early flying machines were based on the flapping motion, all of which
failed.
•
The secret was discovered by Sir George Cayley and later by Otto Lilienthal in
the 1890s. They found that the thrust and lift from a bird's flight are separate.
•
The flapping of a bird's wings is actually directing air mostly backwards. It is
the SHAPE of the wing that causes lift by changing the air pressure above and
below the wing as air rushes over it. This principle is what makes flight
possible on modern airplanes.
Description of Discovery
• December 17, 1903: Kitty Hawk, North Carolina
o the Wright Flyer became the first powered machine to sustain
controlled flight with a pilot aboard.
• Wilbur and Orville Wright
o Between 1899 and 1905, the Wright brothers conducted a
program of aeronautic research in which they experimented with
and refined designs and models that eventually led to the
creation of the first practical airplane.
o All successful airplanes since then have incorporated the basic
design elements of the 1903 Wright Flyer
http://www.nasm.si.edu/wrightbrothers/fly/1900/index.cfm
The physics of flight
There are four basic forces when an airplane is at flight:
1. Lift 2. Thrust 3. Gravity 4. Drag
Only gravity is constant.
• If an airplane is flying at a constant speed, all the forces are in
equilibrium.
Lift:
• The lift on the plane can be achieved through the crosssectional shape wings.
• As the plane flies, the air over the top of the wing flows faster
than the air under the bottom. So the top part of the wing
generates the lower pressure and the bottom part creates the
high pressure. This pressure difference generates the lift on
the airplane in an upward direction.
• The angle of the wings causes the plane to fly at different
angles.
The physics of flight (cont.)
Thrust:
• Propellers are the key to the plane's thrust. The air in front
of the propeller is sucked in and is pushed back toward the
tail. The force generated by this action is thrust. A more
powerful propeller makes the plane go faster. The thrust is
controlled by raising or lowering the rate per minute (rpm)
of the engine by using the throttle.
Drag:
• When an airplane travels using the propeller, an undesired
effect is created: resistance. When the aircraft travels
through the air, its frontal area pushes against the air in
front of it, and the air flowing over the aircraft causes
friction. This is know as drag. So, a narrower and lighter
aircraft goes faster because it reduces drag and resistance.
How the Discovery Impacted Society
• At the start of World War I, air powered aircraft had become
practical for reconnaissance, artillery spotting, and even attacks
against ground positions.
• Aircraft began to transport people and cargo as designs grew larger
and more reliable. Giant rigid airships became the first aircraft to
transport passengers and cargo over great distances.
• After WWII, especially in North America, there was a boom in
general aviation, both private and commercial. Thousands of pilots
were released from military service and many inexpensive warsurplus transport and training aircraft became available.
• Aviation also has an environmental impact. Operating powered
aircraft (from airliners to hot air balloons) releases pollutants and
greenhouse gases such as carbon dioxide(CO2) into the atmosphere.
How the Discovery Impacted Society
(Cont.)
•
Civil aviation includes all non-military flying such as transport aircraft and
general aircraft. Transport aircraft mainly transport hardware and personnel,
and general aviation may include business flights, private aviation,flight
training, ballooning, parachuting, gliding, hang gliding, launched powered
hang gliders, air ambulance, crop dusting, traffic reporting, police air patrols
and forest fire fighting.
•
Military aviation is the use of aircraft enabling warfare. This includes fighter
aircraft, ground-attack aircraft, bombers, transport, surveillance and
missiles. Fighter aircraft destroys other aircraft. Ground-attack aircraft can be
used to provide support for ground troops. Bombers are normally larger,
heavier, and less maneuverable than fighter aircraft. Transport aircraft are
used to transport hardware and personnel. Surveillance aircraft obtain
explosives, but also things like leaflets.
Works Cited
“Air Transport.” Alena Veverka. pond.cz, 2012. Web. 21 Feb. 2012.
&lt;http://alena.veverka.eu/english/lessons.html?id=116&gt;.
Anderson, Kevin. “Reframing climate change: from long-term targets to emission
pathways.” Tyndall’s Centre’s Energy Programme. University of
Manchester. 17 June 2008. Tyndall Centre. Web. 22 Feb. 2012.